Business Segments Information (Business Segments Financial Information) (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016
Segment Reporting Information [Line Items]
Depreciation and amortization	$ 758	$ 636	$ 568
Capital expenditures	617	476	447
Operating Segments [Member] \| Automation Solutions [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	507	400	330
Capital expenditures	295	234	246
Operating Segments [Member] \| Commercial & Residential Solutions [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	215	201	194
Capital expenditures	273	227	177
Operating Segments [Member] \| Climate Technologies [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	171	156	150
Capital expenditures	209	182	133
Operating Segments [Member] \| Tools & Home Products [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	44	45	44
Capital expenditures	64	45	44
Corporate, Non-Segment [Member] \| Corporate and other [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	36	35	44
Capital expenditures	$ 49	$ 15	$ 24

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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- Definition

The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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